The present invention relates to information query systems in general and to interactive query systems more particularly.
With the increasing popularity of the Internet, the global internetwork of networks, many services have come into being that seek to provide information for users of those services. One such service is the GOPHER service, wherein a user is presented with lists of information in the form of menus, and the user is provided with options to select a menu item, which might lead to another menu or to a document of interest, or to initiate a search with a particular set of keywords. The GOPHER system was primarily text based, with the underlying structure being directories on file servers, usually spanning many interlinked and independent servers.
With the advent of a more graphical interface, many such search services continue today, albeit with a graphical interface for use with a Web browser. Here, xe2x80x9cWebxe2x80x9d refers to the hyperlinked collection of dynamic and static hypertext pages available over the Internet using the HTTP (HyperText Transport Protocol) and commonly referred to as the xe2x80x9cWorld Wide Webxe2x80x9d or xe2x80x9cWWWxe2x80x9d, and a Web browser is a client program which allows a user to navigate the Web.
A typical navigation involves setting up an initial query with a set of search terms and viewing the results. If the results are provided as a hypertext page, the user can then select a link on that hypertext page to view the results in more detail.
A disadvantage of searching using search terms is that the English language is imprecise without context and computers are not good at context. For example, asking a human librarian about xe2x80x9cfreedom and values in the Victorian eraxe2x80x9d might yield a book of essays on what the social mores were in the late nineteenth century in Europe and North America. However, performing a search with a search engine against a database of documents might result in the computer returning listings of real estate values for homes with Victorian architecture in Freedom, Calif.
Many providers of search services have attempted to automate the process of determining the proper context of a query so that the correct meaning is ascribed to each term. For example, a server might be programmed to note the ambiguity in the term xe2x80x9cVictorianxe2x80x9d and to further note that xe2x80x9ceraxe2x80x9d refers to a time period and therefore, xe2x80x9cVictorianxe2x80x9d should be interpreted as the time period. Such processing is quite complex and often still fails to understand the context in which the user asks the question.
One embodiment of an information server according to the present invention directs users of the information server to desired sources of information where the desired sources of information are determined, at least in part, based on user input. The information server includes a query input processor, a question processor and an answer processor. The query input processor is used for accepting an initial user query. The question processor processes the initial user query to identify a set of possible well-formed questions selected from the question database, where a well-formed question is a question in the database that is coupled to at least one answer reference. The answer reference is typically either an answer or a pointer to a possible location of an answer.
In a specific embodiment, the information server is coupled to the Internet so that users can pose questions using a Web browser from any Internet-connected device. In some systems, the question processor includes a tokenizer for tokenizing the initial user query into a list of words, a parser for generating a syntactic structure from the list of words, a normalizer for reducing the syntactic structure to a canonical syntactic structure, and a matcher for matching the canonical syntactic structure against a semantic network to obtain a weighted list of well-formed questions representative of possible semantic meanings for the initial user query.